Circuit making and breaking device



May 3 955 E. F. RAWL EI'AL 2,709,726

CIRCUIT MAKING AND BREAKING DEVICE Filed June 4, 1951 /2 INVENTORJ fffiraafye Ffiaw/ BY Jizmes C. Pfaff United States Patent CIRCUHT MAKING AND BREAKING DEVICE Ethradge Forester Raw] and James C. Pfalf, .St. Petersburg, Fla; said Pfatf assignor to said Rawl Application June 4, 1951, Serial No. 229,824

1 Claim. (Cl. 200-16) This invention is directed to an electric circuit making and breaking device and relates especially to a type thereof for simultaneously making and breaking at least two separate and independent circuits.

A particular object of the present invention is to provide an electric circuit coupler by means of which two separate and independent circuits may be quickly opened or closed by a single movable element.

Another object of the invention is to provide a switching device wherein pairs of independent circuit terminals are grouped in a novel manner whereby they are simulta neously bridged by complemental contact elements carried by a single shiftable member, so as to effect the closing at one time of the two separate circuits or the opening of such circuits when the element is oppositely shifted.

A further and more specific object of the invention is to provide a novel circuit switching device which is designed to be particularly advantageous when used in motor vehicles or the like whereby to control current flow from the vehicle battery and also to control current flow from the generator to the battery, as a result of which, in the event of an accident, both circuits can be instantly opened to thereby avoid the possibility of fire.

Other objects and advantages of the invention will become apparent as the description of the same proceeds and the invention will be best understood from a consideration of the following detailed description taken in connection with the accompanying drawing forming a part of the specification, with the understanding, however, that the invention is not to be limited to the exact details of construction shown and described since obvious modifications will occur to a person skilled in the art.

In the drawing:

Figure 1 is a view looking toward the control handle of the switch structure of the present invention.

Figure 2 is a sectional view taken substantially on the line 22 of Figure 1.

Figure 3 is a sectional view taken substantially on the line 33 of Figure 1.

Figure 4 is a view in plan of the terminal block showing the spaced terminals and conductors connected therewith.

Figure 5 is a view in side elevation of the central portion of the terminal block showing the locking slot for the coupler, in one of the outer terminals.

Referring now more particularly to the drawing the numeral generally designates a flat insulation body which may be identified generally as the terminal block and upon which the hereinafter described metal current conducting strips and spaced terminals, are carried.

As shown in Figure 4 the terminal block is preferably of elongated rectangular design and secured longitudinally thereof from each end is a current conducting strip 12, such strips being secured to the block by rivets 14 and also having passed therethrough and through the block, the wire binding posts 16 with which may be connected current conductors, not shown.

'ice

The conductor strips 12 extend toward the transverse center of the block 10 and the inner end of each is integrally formed with or connected with a semi-cylindrical terminal element 18 which forms a part of a longitudinally divided or split cylinder which is generally designated 20. As shown most clearly in Figures 4 and 5 the semicylindrical parts 18 are in edge to edge spaced relation, providing the passage or slot 21 therebetween and one lonigtudinal edge of each part 18 has a locking notch 22 formed therein for the purpose hereinafter described. These notches 22 are in the remotely related edges of the two cylinders.

As is also clearly shown in Figure 5 the inner ends of the conductor strips 12, where they join the semi-cylindrical parts 18, are angled or turned slightly as at 23, whereby the parts 18 are held in spaced relation with the adjacent face of the terminal block 10.

Disposed transversely to the terminal strips 12 are two terminal strips 24 which extend from opposite side edges of the block and are secured to the block by the rivets 25. Each of these conductor strips 24 carries a wire binding screw 26 on an end which is spaced from the back of the conductor block 10 as shown in Figures 2 and 3. The conductor strips 24 have their end portions on the front or face of the terminal block 10 extended between the block 10 and the ends of the semi-cylindrical parts 18 and terminate in closely spaced relation at the center of the cylinder 20 as shown in Figure 4. The adjacent or opposed ends of the conductor strips 24 terminate in the substantially semi-circular prongs 27 which are in slightly convergent relation as is clearly shown in Figure 3 whereby the free ends of the prongs are somewhat closer together than the base portions thereof. These semi-circular prongs 27 are concentric with the semicylindrical parts 18 or with the cylinder 20 which the parts 18 form.

The coupler by means of which the terminal parts 18 and the terminal prongs 27 are electrically connected so that the conductors 12 will complete one circuit and the conductors 24 will complete another circuit, is generally designated 28. This coupler 28 coacts with a housing 'by a number of such screws.

which covers the terminal parts and prongs and which is generally designated 29. As shown the housing 29 is in the form of a box having an open side which receives the terminal block 10 to which it is secured in any suitable manner as, for example, by a screw 30 or The wall of the box 29 opposite from the terminal block 10, is formed to provide the outwardly extending sleeve 31 which is coaxial with the cylinder 20.

The coupler 28 comprises an elongate circular bar 32 which is of a diameter to fit snugly in the collar 31 as shown. The outer end of this coupler bar carries a head or handle 33.

The inner end of the coupler bar carries two spaced concentric metal collars 34 which are secured together in the desired concentric spaced relation and to the end of the bar 32, by the transverse pin 35, the ends of which pin bridge the space between the collars 34 as clearly shown in Figure 3. An additional securing means for the collars comprises a second pin 36 which extends at right angles to the pin 35 and is near the back ends of the collars 34. As is also shown in Figures 2 and 3 the spaced concentric collars 34 are of a diameter whereby the outside diameter of the outside collar is the same as the bar 32 whereby the collars can pass easily through the sleeve 31.

The spacing between the collars 34 is approximately equal to the thickness or" the semi-cylindrical parts 18 and the circular space between the collars is of the same diameter as the sleeve 20 whereby when the coupler bar 32 is inserted through the sleeve 31 the parts 18 of the cylinder 20 will be snugly received between the collars and when the coupler bar is inserted in the proper manner the portions of the pin 35 bridging the space between the collars will enter the slots 21 between the terminal portions 18 and when the coupler has been pushed inwardly to the limit of its position the end portions of the pin 35 will be in line with the locking notches 22 and can be entered into the notches by rotating the bar.

In order to indicate when the bar 32 is properly held to enter the ends of the pin 35 into the slots 21, the head 33 may be provided with a suitable indication such, for example, as the arrow 37 shown in Figure 1 or, obviously, any other suitable means may be employed.

In addition to the two concentric spaced collars 34 which function to electrically couple the terminals 13 whereby a circuit in which the conductor strips 12 are connected, may be completed, means is provided for electrically coupling, at the same time, the terminal prongs 27. Such means comprises a short thimble 38 of current conducting material, engaged on the reduced axial extension 39 of the bar 32 concentrically with the collars 34. This thimble 38 is of an outside diameter materially less than the inside diameter of the inner one of the collars 34 so that proper electrical spacing is maintained between the thimble and the adjacent collar and the thimble is held in place in a suitable manner as, for example, by a transverse pin 4t which passes therethrough and through the extension 39.

As shown in Figures 2 and 3 the interior diameter of the thimble 38 is slightly less than the diameter of the circle defined by the base portions of the prongs 27 with which circle the thimble 38 is concentric so that when the coupler bar 32 is introduced through the housing box sleeve 31 and projected axially onto the cylinder 28, the terminal prongs 27 will enter the advancing end of the thimble 38 and will be brought firmly into electrical connection therewith. By tapering and converging the prongs 27 it will be readily seen that there will be a self cleaning action performed by the thimble on the terminal prongs 27 each time the electrical connection is made so that a good contact is assured at all times.

While the present switch structure may be of service in many connections, one use to which it may be advantageously put is in a motor vehicle where the conductors 12 may be made a part of the battery cable and the conductors 24 may be connected in the generator circuit by which current is supplied to the battery when the motor vehicle is in operation. Thus it will be seen that the switch device may be used as a theft preventing means by withdrawing the coupler 28 when the car is left or it may be employed as a safety means for preventing fire in the event of an accident, by reason of the fact that the coupler can be quickly withdrawn so as to open both circuits.

As previously stated the present invention may have a variety of uses and accordingly it is to be understood that although it has been described particularly with regard to electric circuits of an automobile, it is not restricted to such use.

We claim:

in an electric circuit making and breaking device, the combination of a circuit terminal member comprising a flat insulated base, pairs of stationary contact elements mounted on said base, each pair constituting the terminals of an independent circuit, the elements of one pair being spacedly aligned metal strips having their adjacent end portions upturned and reversely curved into semi-circular form and defining a circle, the elements of the other pair being spacedly aligned metal strips disposed in right angular relation with respect to the said one pair and having their adjacent end portions upturned, reversely curved and slightly inclined toward each other, the latter end portions being disposed centrally with respect to the first end portions, a housing supported on said base and having a top wall provided with a central opening, a sleeve attached to said top wall concentric with said opening, and a coupler member comprising an elongated insulated bar of circular cross-section slidably supported in said sleeve, a pair of concentrically disposed cylindrical contact elements mounted on the outer side of the inner end of said bar and spaced apart to define concentric circles to engage over the end portions of the said one pair of contact elements in a manner to bridge the same when the bar is moved inwardly toward said base, a cylindrical contact element seated in the inner end of said bar in concentric relation with respect to the other contact elements carried thereby and having its inner end closed and its outer end open for bridging engagement over the end portions of the said other pair References Cited in the file of this patent UNITED STATES PATENTS 1,080,058 Hart Dec. 2, 1913 1,905,843 Foulke a Apr. 25, 1933 2,297,374 Tingle Sept. 29, 1942 2,461,268 Goldfield Feb. 8, 1949 2,548,457 Wilson Apr. 10, 1951 

